Method of manufacturing an electrode active material particle for a rechargeable battery

Abstract

A method of manufacturing an electrode active material particle for a rechargeable battery wherein a layer of an active material capable of being alloyed with Li is formed on a surface of a metal particle incapable of being alloyed with Li and then a heat treatment is conducted to diffuse the active material into the metal particle so that the resulting active material particle has a concentration profile in which a concentration of a metal element of the metal particle decreases from an interior toward the surface.

1. A method of manufacturing an electrode active material particle for a rechargeable battery characterized by forming a layer of an active material capable of being alloyed with Li on a surface of a metal particle incapable of being alloyed with Li and then conducting a heat treatment to diffuse said active material into said metal particle so that the resulting active material particle has a concentration profile in which a concentration of a metal element of said metal particle decreases from an interior toward the surface. 
     
     
       2. The method of manufacturing an electrode active material particle for a rechargeable battery according to  claim 1 , characterized in that said active material is at least one selected from Si, Ge, Sn, Al and In. 
     
     
       3. The method of manufacturing an electrode active material particle for a rechargeable battery according to  claim 1 , characterized in that a metal element of said metal particle is Cu. 
     
     
       4. The method of manufacturing an electrode active material particle for a rechargeable battery according to  claim 1 , characterized in that said active material substantially consists of Si, and a metal element of said metal particle is Cu. 
     
     
       5. The method of manufacturing an electrode active material particle for a rechargeable battery according to  claim 1 , characterized in that said active material particle is used as a negative electrode active material. 
     
     
       6. A method of manufacturing an electrode active material particle for a rechargeable battery characterized by forming a layer containing at least one selected from Si, Ge, Sn, Al and In as the active material, on a surface of a metal particle containing Cu and then conducting a heat treatment to diffuse said active material into said metal particle so that said active material particle has a concentration profile in which a concentration of said Cu decreases from an interior toward the surface. 
     
     
       7. The method of manufacturing an electrode active material particle for a rechargeable battery according to  claim 6 , characterized in that said active material particle is used as a negative electrode active material.